Abstract

Photoluminescence from InPquantum dots within a GaP matrix is investigated as a function of magnetic field. By fitting the magnetoluminescence data to the energy states of the electrons and holes confined in quantum dots in a perpendicular magnetic field, the electron-hole reduced effective mass is determined to be . The diamagnetic shift in the luminescence peak gives an average exciton radius of about 5 nm, smaller than the dot radius. These results indicate that the recombining electrons are primarily composed of states originating from the InP valley although the conduction band discontinuity between the InP and the GaP barrier is expected to be very small or even negative.

Received 28 May 2009Accepted 18 September 2009Published online 13 October 2009

Acknowledgments:

The authors thank S. George and LNCMI technical staff for their support, M. Goiran and J. Gonzalez for fruitful discussions. Part of this work was supported by EuroMagNet-FP6 (Project No. TSE15-207, Contract No. R113-CT2004-506239).